This invention relates generally to portable heating appliances and, more particularly, is directed to a novel hair roller heating device.
Women often use hair rollers to set their hair with particular curls, waves and the like. It has been found that this is accomplished more easily if the hair rollers are flexible and heated. Accordingly, hair rollers have been developed comprised of a flexible plastic tube surrounding a flexible metal coil spring. In the unflexed state, the coil spring forces the plastic tube into a linear arrangement.
In addition, devices for heating these hair rollers have also been developed, whereby the metal coil spring is heated indirectly. For example, one such hair roller heating device is sold by Conair Corporation, 11 Executive Avenue, Edison, N.J. 08817 under the trademark "Hot Sticks". With this device, tight curls, soft curls and body waves can be achieved.
The Conair device includes a hollow housing having a plurality of spaced openings in the upper surface thereof through which the hair rollers can be inserted. Heating means is positioned within the housing and generally includes a plurality of metal tubes positioned with a vertical orientation in the housing below the openings. Thus, the hair rollers fit through the openings in the housing and are lodged in the metal tubes. The metal tubes, however, have separate heating blankets surrounding them, each heating blanket being electrically heated, thereby requiring an electric supply cord and a plug connected to the electric heating means. This is disadvantageous from a number of respects. First, if there is no electric outlet, heating can not be performed. Second, the use of an electric cord restricts placement of the device and may be dangerous if it becomes tangled or the like. Third, the construction is complicated due to the requirement of the electric heating blankets.
Curling irons which heat the barrel with a portable fuel source, such as a catalytic gas, are also well known. The catalytic converters thereof are powered by butane or similar type gases which may take the form of replaceable or refillable cartridges. Such portable curling irons are widely used, and may be conveniently used almost anywhere.
Catalytic burners for portable curling irons suffer from several disadvantages. First, they are slow to heat and expensive to manufacture, which are clearly undesirable. Additionally, if the temperature runs too high, the platinum catalyst sinters, reducing surface area, which reduces life.
Still further, catalytic converters can suffer from "hot spots" which can render them dangerous.